1
00:00:01,920 --> 00:00:06,320
Speaker 1: Welcome to brain Stuff production of I Heart Radio. Hi

2
00:00:06,440 --> 00:00:09,160
Speaker 1: brain Stuff Lauren boge obam here with a classic brain

3
00:00:09,200 --> 00:00:13,320
Speaker 1: Stuff episode. As we often discuss on this show, human

4
00:00:13,360 --> 00:00:18,480
Speaker 1: bodies are gloriously weird things that science still doesn't entirely understand.

5
00:00:19,120 --> 00:00:23,640
Speaker 1: For example, allergies. They're an immune system response that's influenced

6
00:00:23,640 --> 00:00:26,720
Speaker 1: by everything from our genes to what we're exposed to

7
00:00:26,880 --> 00:00:30,639
Speaker 1: during our first months of life. Today's episode deals with

8
00:00:30,680 --> 00:00:33,240
Speaker 1: how even the season it was when you were born

9
00:00:33,440 --> 00:00:38,360
Speaker 1: can make a difference. Hey, brain Stuff, Lauren bog obam here,

10
00:00:38,880 --> 00:00:41,360
Speaker 1: people born in the fall and winter are more likely

11
00:00:41,400 --> 00:00:44,280
Speaker 1: to have allergies than people born in the spring and summer.

12
00:00:44,720 --> 00:00:46,960
Speaker 1: While that might be news to you, it certainly was

13
00:00:47,000 --> 00:00:50,080
Speaker 1: to me. The scientific community has known about it for years,

14
00:00:50,400 --> 00:00:52,920
Speaker 1: and a recent study published in the European Journal of

15
00:00:52,960 --> 00:00:56,800
Speaker 1: Allergy and Clinical Immunology set out to discover why it happens.

16
00:00:57,680 --> 00:01:00,440
Speaker 1: Many of us have a unique physical identify or maybe

17
00:01:00,480 --> 00:01:03,520
Speaker 1: a noticeable birth mark. We also have certain markers on

18
00:01:03,560 --> 00:01:06,080
Speaker 1: our DNA that can help determine things like our weight

19
00:01:06,120 --> 00:01:08,640
Speaker 1: and height, our mood swings, and even our risk for

20
00:01:08,680 --> 00:01:13,040
Speaker 1: some conditions like schizophrenia. The researchers found out that those markers,

21
00:01:13,080 --> 00:01:16,280
Speaker 1: called epigenetic marks, can help determine whether we're at risk

22
00:01:16,440 --> 00:01:20,199
Speaker 1: for allergies. We spoke with Dr Gabrielle Lockett, lead author

23
00:01:20,240 --> 00:01:23,680
Speaker 1: of the study, via email. She said epigenetic marks are

24
00:01:23,680 --> 00:01:26,679
Speaker 1: a way to regulate the expression of genes without altering

25
00:01:26,720 --> 00:01:30,640
Speaker 1: the underlying DNA sequence. A gene expression is a process

26
00:01:30,640 --> 00:01:34,840
Speaker 1: where information stored in our DNA is translated into instructions

27
00:01:34,880 --> 00:01:38,920
Speaker 1: for making proteins or other molecules. Lockett, who is a

28
00:01:38,959 --> 00:01:42,320
Speaker 1: postdoctoral research fellow in the Faculty of Medicine at England's

29
00:01:42,360 --> 00:01:45,840
Speaker 1: University of Southampton, says that researchers have long known that

30
00:01:45,880 --> 00:01:50,160
Speaker 1: your birth season, as well as certain environmental exposures like smoking, famine,

31
00:01:50,240 --> 00:01:53,720
Speaker 1: or even your social environment, are associated with certain epigenetic

32
00:01:53,760 --> 00:01:58,040
Speaker 1: marks and can alter gene expression. They just didn't know why.

33
00:01:58,240 --> 00:02:01,320
Speaker 1: She said epigenetic marks were a good candidate for the

34
00:02:01,440 --> 00:02:05,040
Speaker 1: connecting mechanism between birth season and allergies because they can

35
00:02:05,080 --> 00:02:08,840
Speaker 1: be altered by environmental exposures, can influence gene expression, and

36
00:02:08,919 --> 00:02:12,720
Speaker 1: can last many years. Lockett and her team scanned DNA

37
00:02:12,840 --> 00:02:15,799
Speaker 1: samples from three hundred and sixty seven eighteen year olds

38
00:02:15,840 --> 00:02:17,960
Speaker 1: who were born on the Isle of Wight in England.

39
00:02:18,480 --> 00:02:22,440
Speaker 1: They paid particular attention to certain markers called DNA methylation

40
00:02:22,480 --> 00:02:26,160
Speaker 1: in the samples. DNA methylation is one type of epigenetic mark.

41
00:02:26,600 --> 00:02:29,840
Speaker 1: Methyl groups help cells reproduce normally, and they can literally

42
00:02:29,880 --> 00:02:33,560
Speaker 1: turn genes on or off. When your methyl groups are depleted,

43
00:02:33,840 --> 00:02:36,799
Speaker 1: bad genes like those that cause cancer are turned on.

44
00:02:37,800 --> 00:02:40,720
Speaker 1: Researchers wanted to know whether certain markers could be linked

45
00:02:40,760 --> 00:02:43,200
Speaker 1: to the time of year a person was born, and

46
00:02:43,280 --> 00:02:47,760
Speaker 1: whether those people experience allergies like xzema or asthma. Lockett said,

47
00:02:48,040 --> 00:02:51,400
Speaker 1: we found that yes, DNA methylation at certain places in

48
00:02:51,440 --> 00:02:55,320
Speaker 1: the genome is consistently associated with season of birth. We

49
00:02:55,400 --> 00:02:58,320
Speaker 1: went on to discover that these birth seasonal epigenetic marks

50
00:02:58,360 --> 00:03:01,760
Speaker 1: are associated with gene expression and could potentially provide a

51
00:03:01,800 --> 00:03:05,840
Speaker 1: link to allergic disease. Luckett says her team found similar

52
00:03:05,880 --> 00:03:07,920
Speaker 1: results when they duplicated the study with a group of

53
00:03:07,919 --> 00:03:10,440
Speaker 1: eight year olds from Holland, but the markers were not

54
00:03:10,560 --> 00:03:13,880
Speaker 1: present when the team tested a group of newborns. Lackett

55
00:03:13,960 --> 00:03:17,600
Speaker 1: says this suggests that epigenetic markers arise after birth or

56
00:03:17,639 --> 00:03:20,959
Speaker 1: maybe even as a result of one's environment. The link

57
00:03:21,000 --> 00:03:24,000
Speaker 1: between birth month, and allergy risk applies to all kinds

58
00:03:24,040 --> 00:03:27,680
Speaker 1: of allergies, Luckett said. For decades, studies have shown that

59
00:03:27,760 --> 00:03:30,079
Speaker 1: people born in autumn and winter are at an increased

60
00:03:30,160 --> 00:03:33,640
Speaker 1: risk of not only rhinitis hay fever, but also food allergy,

61
00:03:33,720 --> 00:03:37,960
Speaker 1: asthma and eczema. She continued, One large Dutch study found

62
00:03:38,000 --> 00:03:40,680
Speaker 1: that people born in ottuman winter were at increased risk

63
00:03:40,720 --> 00:03:43,960
Speaker 1: of having immune responses to non seasonal allergies such as

64
00:03:44,000 --> 00:03:46,840
Speaker 1: egg white and cow's milk, as well as two seasonal

65
00:03:46,840 --> 00:03:50,840
Speaker 1: allergies like pollen, cat dog and house dust mighte. This

66
00:03:50,920 --> 00:03:53,480
Speaker 1: suggests that season of birth is associated with a person's

67
00:03:53,560 --> 00:03:56,920
Speaker 1: risk of allergy in general. The effect is not restricted

68
00:03:56,960 --> 00:04:01,480
Speaker 1: to seasonal allergies. So why would your birth month affect

69
00:04:01,520 --> 00:04:04,720
Speaker 1: your risk of allergies? Lock It lists some of the theories.

70
00:04:05,320 --> 00:04:08,360
Speaker 1: Lower sunlight exposure during autumn and winter might reduce vitamin

71
00:04:08,480 --> 00:04:11,080
Speaker 1: D levels, which have a known connection to allergy risk.

72
00:04:11,600 --> 00:04:14,720
Speaker 1: Seasonal fluctuations in the levels of certain allergies such as

73
00:04:14,760 --> 00:04:17,200
Speaker 1: pollen or house dust mites, or the age at which

74
00:04:17,240 --> 00:04:20,599
Speaker 1: baby gets their first rhinovirus hay fever infection more common

75
00:04:20,640 --> 00:04:24,400
Speaker 1: in winter, may also contribute to allergic disease risk. Also,

76
00:04:24,560 --> 00:04:27,600
Speaker 1: the seasonal availability of different fruits and vegetables eaten by

77
00:04:27,600 --> 00:04:30,040
Speaker 1: the pregnant mother could alter the nutrition that baby is

78
00:04:30,080 --> 00:04:33,640
Speaker 1: born in different seasons received during important stages of early development.

79
00:04:34,520 --> 00:04:37,640
Speaker 1: But of course our bodies are complicated and more research

80
00:04:37,720 --> 00:04:46,200
Speaker 1: is needed before we can know for sure. Today's episode

81
00:04:46,240 --> 00:04:49,280
Speaker 1: is based on the article marked at birth Your birth month,

82
00:04:49,480 --> 00:04:52,880
Speaker 1: allergies and DNA are linked on how stuff works dot com,

83
00:04:52,920 --> 00:04:55,840
Speaker 1: written by Nicole bays Moore. Brain Stuff is production of

84
00:04:55,880 --> 00:04:58,000
Speaker 1: by Heart Radio in partnership at house stuff work dot

85
00:04:58,040 --> 00:05:00,800
Speaker 1: com and it is produced by Tyler Klang. Four more

86
00:05:00,839 --> 00:05:03,600
Speaker 1: podcasts my heart Radio, visit the I heart Radio app,

87
00:05:03,720 --> 00:05:06,520
Speaker 1: Apple Podcasts, or wherever you listen to your favorite shows